Abstract: The high volume fraction SiCp/Mg composites were fabricated by vacuum pressure infiltration process.The results show that infiltration was effectively promoted by vacuum pressure infiltration process,which also avoids the gas and the inclusion binds.The preform of a single minimum SiC particle with size of 32Lm and volume fractions of 58.21% is successful infiltrated under the pressure of 300kPa,holding time of 5min and temperature of 973K.The analysis results by OM and XRD indicate that SiC particles are uniformly distributed in the magnesium matrix without casting defects,such as bubble,shrinkage,inclusion.